1. Field of the Invention
The invention relates generally to the field of computer systems and, more specifically, to a technique for determining whether a server-side host supports a command provided by a client-side host.
2. Description of the Related Art
Computer systems include host computers that communicate with one another via a network to run network applications. Typically, software is distributed and run on two or more hosts to realize the application. The network applications have application-layer protocols that define the format and order of the messages that are exchanged between the hosts, and what actions to take when a message is transmitted or received. In particular, a network application typically includes a client side and a server side. In this case, the application may be referred to as a client/server application. A client side on one host may communicate with a server side on another host. The client is usually the host that initiates a communication or session with another host.
However, difficulties arise when the client host and server host are running different versions of the network application or other software. In this case, the client may provide a command to the server requesting it to perform a specific function that the server does not support. Various approaches have been developed to address this problem. For example, the client may send additional data to the server such as a codeword that identifies the version the client is using. However, this approach lacks generality and requires that a special protocol for coding and decoding the version data be implemented.